Method of manufacturing winged coil structure

ABSTRACT

A method of manufacturing a winged coil structure is provided. The method includes preparing an upper flexible plate having a middle region and two side regions bordering the middle region; preparing a dielectric layer with a lateral size of the dielectric layer being the same as a lateral size of the middle region of the upper flexible plate; preparing a lower flexible plate having a middle region and two side regions bordering the middle region; preparing a bottom flexible plate attached to the lower surface of the lower flexible plate to form a stack body; and performing a process of thermal pressing to sequentially from bottom to top stack and combine the stack body, the dielectric layer, and the upper flexible plate as a multiple layered stack structure via a press mold.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a Division of application Ser. No. 15/811,317, filedon Nov. 13, 2017, which is a Continuation Application of U.S.application Ser. No. 14/877,981 filed on Oct. 8, 2015. The priorapplications are herewith incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention generally relates to a method of manufacturing thewinged coil structure, and more specifically to a method ofmanufacturing the winged coil structure having upper and lowerconnection pads combined by connection plugs through thermal pressing,and provided with notched lines at upper flexible plate to facilitatetwo side regions of the upper flexible plate to bend for implementing aflexible, bendable feature, and a function of magnetic induction.

2. The Prior Arts

In general, any electric or electronic device needs a circuit board toaccommodate and connect various elements. With good mechanical strengthand electrical insulation, rigid circuit boards like epoxy boards havebeen widely used. However, the general rigid circuit board is flat andnot bendable. As a result, the traditional rigid board sometimes failsto meet the specific geometry of the actual application for savingspace. For instance, mobile phones provide very limited available areato install electric or electronic elements. Thus, it is needed for aplate with workability of flexibility and bending. This is so calledflexible boards. The manufacturing processes for the flexible boardshave been developed for years, and very mature and reliable.

Additionally, many circuits need the inductors to exhibit inductiveproperty, and the specific coils like magnetic induction coils are used.In the traditional technology, copper metal or alloy is usually employedto form helical patterns as the coils by etching or electroplating, andthe mechanical or laser drilling process is then used to formthrough-holes. The coils and the flexible plates are often provided bydifferent manufacturers and the respective through-holes are formedbefore shipment. It is needed to attach the coils and the flexibleplates to form the circuit board as desired. As a result, the additionalprocess of attaching is required. While the coils being attached to therespective flexible plate, the problem of alignment mismatch oralignment tolerance for the respective through-holes may adverselyaffect the whole electrical performance of the circuit board.

Moreover, several coils are usually manufactured on the same surface ofthe flexible plate in traditional process to enlarge the effective rangeof magnetic induction as much as possible. The overall occupied area,however, increases, and it is adverse to the actual application.

Therefore, it is greatly needed to provide a new winged coil structureand a method of manufacturing the same. The connection plug possessingthe aspect of workability of thermal process is employed to tightlycombine the upper and lower connection pads, and the notched lines onthe upper flexible plate help two side regions of the flexible platebeing easily bent upwards or downwards. The winged coil structureexhibits the flexible and bendable feature. In particular, the upper,lower and bottom magnetic induction coils are integrated as a multiplelayers stack structure without concern about alignment tolerance for therespective holes while combining the individual coil and plate. Theeffect of magnetic induction is greatly enhanced, thereby overcoming theabove problems in the prior arts.

SUMMARY OF THE INVENTION

In view of these, one embodiment of the disclosure provides a method ofmanufacturing a winged coil structure for providing a function ofmagnetic induction and a flexible and bendable feature. The methodcomprises preparing an upper flexible plate having a middle region andtwo side regions bordering the middle region, and provided with at leastone upper magnetic induction coil, at least one upper connection pad,and at least one connection plug, the at least one upper magneticinduction coil and the at least one upper connection pad beingelectrically connected and embedded in the middle region of the upperflexible plate and close to an upper surface of the upper flexibleplate, the at least one connection plug being provided on the lowersurface of the middle region of the upper flexible plate and attached toa bottom of the corresponding upper connection pad; preparing adielectric layer with a lateral size of the dielectric layer being thesame as a lateral size of the middle region of the upper flexible plate;preparing a lower flexible plate having a middle region and two sideregions bordering the middle region, and provided with at least onelower magnetic induction coil and at least one lower connection pad, theat least one lower magnetic induction coil and the at least one lowerconnection pad being electrically connected and embedded in the middleregion of the lower flexible plate and close to a lower surface of thelower flexible plate; and performing a process of thermal pressing tosequentially from bottom to top stack and combine the lower flexibleplate, the dielectric layer, and the upper flexible plate as a multiplelayered stack structure via a press mold, the at least one connectionplug being formed of an electrically conductive metal material,configured to penetrate the dielectric layer, and provided between thecorresponding upper and lower connection pads such that the at least oneconnection plug combines the corresponding upper and lower connectionpads after the process of thermal pressing to form electricalconnection; wherein a notched line is provided along each adjacency ofthe lower surface of the upper flexible plate and the lower flexibleplate, the notched line has a trench recessing upwards or inwards suchthat the two side regions of the upper flexible plate are bendableupwards or downwards, and the dielectric layer is not extended to thenotched line.

In one embodiment, a middle through-hole is provided at the middleregion of the upper flexible plate, at least one middle through-hole isprovided at a middle region of the dielectric layer, and a middlethrough-hole is provided at the middle region of the lower flexibleplate.

In one embodiment, the respective middle through-holes of the lowerflexible plate, the dielectric layer, and the upper flexible plate arevertically aligned in the multiple layered stack structure. The at leastone connection plug is configured to penetrate the at least one middlethrough-hole of the dielectric layer.

In one embodiment, the upper flexible plate and the lower flexible plateare formed of a resin or plastic material. The at least one connectionplug is formed of copper, tin, copper alloy, or tin alloy, and has ashape of ball, column, or block.

In one embodiment, the upper flexible plate is further provided with atleast one gold finger, and the at least one gold finger is provided onlower surfaces of the two side regions of the upper flexible plate.

In one embodiment, the upper magnetic induction coil, the upperconnection pad, the lower magnetic induction coil, the lower connectionpad, and the at least one gold finger are formed of the same ordifferent electrical conductive material. The electrical conductivematerial comprises copper, copper alloy, or gold, and the dielectriclayer is formed of a dielectric material.

In one embodiment, base surfaces of the two side regions of the upperflexible plate are attached to or covered by an external dielectriclayer, and the external dielectric layer is formed of a dielectricmaterial the same as or different from the dielectric material of thedielectric layer.

Another embodiment of the disclosure provides a method of manufacturinga winged coil structure for providing a function of magnetic inductionand a flexible and bendable feature. The method comprises preparing anupper flexible plate having a middle region and two side regionsbordering the middle region, and provided with at least one uppermagnetic induction coil, at least one upper connection pad, and at leastone connection plug, the at least one upper magnetic induction coil andthe at least one upper connection pad being electrically connected andembedded in the middle region of the upper flexible plate and close toan upper surface of the upper flexible plate, the at least oneconnection plug being provided on the lower surface of the middle regionof the upper flexible plate and attached to a bottom of thecorresponding upper connection pad; preparing a dielectric layer with alateral size of the dielectric layer being the same as a lateral size ofthe middle region of the upper flexible plate; preparing a lowerflexible plate having a middle region and two side regions bordering themiddle region, and provided with at least one lower magnetic inductioncoil and at least one lower connection pad, the at least one lowermagnetic induction coil and the at least one lower connection pad beingelectrically connected and embedded in the middle region of the lowerflexible plate and close to a lower surface of the lower flexible plate;preparing a bottom flexible plate attached to the lower surface of thelower flexible plate to form a stack body, the bottom flexible platehaving a middle region and two side regions bordering the middle region,and provided with at least one bottom magnetic induction coil and the atleast one bottom connection pad, the at least one bottom magneticinduction coil and the at least one bottom connection pad beingelectrically connected, embedded in the middle region of the bottomflexible plate, and close to a lower surface of the bottom flexibleplate; and performing a process of thermal pressing to sequentially frombottom to top stack and combine the stack body, the dielectric layer,and the upper flexible plate as a multiple layered stack structure via apress mold, the at least one connection plug being formed of anelectrically conductive metal material, configured to penetrate thedielectric layer, and provided between the corresponding upper and lowerconnection pads such that the at least one connection plug combines thecorresponding upper and lower connection pads after the process ofthermal pressing to form electrical connection; wherein a notched lineis provided along each adjacency of the lower surface of the upperflexible plate and the lower flexible plate, the notched line has atrench recessing upwards or inwards such that the two side regions ofthe upper flexible plate are bendable upwards or downwards, and thedielectric layer is not extended to the notched line.

In one embodiment, a middle through-hole is provided at the middleregion of the upper flexible plate, at least one middle through-hole isprovided at a middle region of the dielectric layer, a middlethrough-hole is provided at the middle region of the lower flexibleplate, and a middle through-hole is provided at the middle region of thebottom flexible plate.

In one embodiment, the respective middle through-holes of the bottomflexible plate, the lower flexible plate, the dielectric layer, and theupper flexible plate are vertically aligned in the multiple layeredstack structure, and the at least one connection plug is configured topenetrate the at least one middle through-hole of the dielectric layer.

In one embodiment, the upper flexible plate, the lower flexible plate,and the bottom flexible plate are formed of a resin or plastic material,and wherein the at least one connection plug is formed of copper, tin,copper alloy, or tin alloy, and has a shape of ball, column, or block.

In one embodiment, the upper flexible plate is further provided with atleast one gold finger, and the at least one gold finger is provided onlower surfaces of the two sides regions of the upper flexible plate.

In one embodiment, the upper magnetic induction coil, the upperconnection pad, the lower magnetic induction coil, the lower connectionpad, the bottom magnetic induction coil, the bottom connection pad, andthe at least one gold finger are formed of the same or differentelectrical conductive material. The electrical conductive materialcomprises copper, copper alloy, or gold, and the dielectric layer isformed of a dielectric material.

In one embodiment, base surfaces of the two side regions of the upperflexible plate are attached to or covered by an external dielectriclayer, and the external dielectric layer is formed of a dielectricmaterial the same as or different from the dielectric material of thedielectric layer.

In one embodiment, the method further comprises prior to the process ofthermal pressing, supporting a bottom of the bottom flexible plate by anauxiliary stuff, wherein the auxiliary stuff is larger than or equal tothe upper flexible plate and has two projecting parts at two endsaligned to the at least one gold finger, so that the two side regions ofthe upper flexible plate and the dielectric layer are supported by theauxiliary stuff during the process of thermal pressing; removing theauxiliary stuff after the process of thermal pressing; and covering acovering layer on the upper surface of the upper flexible plate, thelower surface of the lower flexible plate, and a surrounding area of theat least one gold finger, wherein the covering layer is formed of anelectrical insulation material with transparency or opaqueness.

Since the upper and lower magnetic induction coils are close to theupper surface of the upper flexible plate and the lower surface of thelower flexible plate, respectively, the effect of magnetic induction isgreatly enhanced with limited available area. Furthermore, the notchedlines of the present invention help the two side regions of the flexibleplate being easily bent upwards or downwards without damage to the upperand lower magnetic induction coils embedded. Thus, the application fieldof the present invention is widely expanded and industrial utility inthe current market is obviously improved.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be apparent to those skilled in the art byreading the following detailed description of a preferred embodimentthereof, with reference to the attached drawings, in which:

FIG. 1 is a top view showing a winged coil structure according to thefirst embodiment of the present invention;

FIG. 2 is a cross sectional view showing the winged coil structure inFIG. 1;

FIG. 3 is a cross sectional view showing a winged coil structureaccording to the second embodiment of the present invention;

FIG. 4 is a flowchart showing a method of manufacturing the winged coilstructure according to the third embodiment of the present invention;

FIGS. 5A to 5D are views showing the respective steps of the methodaccording to the third embodiment of the present invention;

FIG. 6 is a flowchart showing a method of manufacturing the winged coilstructure according to the fourth embodiment of the present invention;and

FIGS. 7A to 7E are views showing the respective steps of the methodaccording to the fourth embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The accompanying drawings are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this specification. The drawings illustrate embodiments of theinvention and, together with the description, serve to explain theprinciples of the invention.

Please refer to FIGS. 1 and 2. FIG. 1 illustrates a top view of thewinged coil structure according to the first embodiment of the presentinvention, and FIG. 1 shows a cross sectional view of the winged coilstructure. As shown in FIGS. 1 and 2, the winged coil structure of thefirst embodiment generally comprises at least one upper magneticinduction coil 10, at least one upper connection pad 10A, at least onelower magnetic induction coil 11, at least one lower connection pad 11A,an upper flexible plate 20A, a lower flexible plate 20B, at least onegold finger 22, a dielectric layer 24 and at least one connection plug26.

The upper flexible plate 20A and the lower flexible plate 20B are formedof flexible substrates with electrical insulation material,respectively, like resin or plastic material. The dielectric layer 24 isprovided between the upper flexible plate 20A and the lower flexibleplate 20B. The upper flexible plate 20A is configured on an uppersurface of the dielectric layer 24, and the lower flexible plate 20B isbeneath a lower surface of the dielectric layer 24. In particular, thelateral size of the upper flexible plate 20A is larger than the lateralsize of the lower flexible plate 20B. Thus, the winged coil structure ofthe first embodiment has a thicker middle part projecting downward andtwo thinner side parts bordering the middle part so as to form a shapeof two wings.

In addition, the upper surface of the winged coil structure is smoothand planar, but the lower surface of the winged coil structure has aprojecting middle area. The middle part of the winged coil structure hasa middle through-hole H, and the dielectric layer 24 sandwiched betweenthe upper flexible plate 20A and the lower flexible plate 20B ispenetrated by the middle through-hole H.

Specifically, the at least one upper magnetic induction coil 10 and theat least one lower magnetic induction coil 11 are embedded in the upperflexible plate 20A and the lower flexible plate 20B, respectively, andconfigured close to the upper surface of the upper flexible plate 20Aand the lower surface of the lower flexible plate 20B, respectively.Each of the upper magnetic induction coil 10 and the lower magneticinduction coil 11 has a helical shape, and is provided around the middlethrough-hole H and separated by the dielectric layer 24.

The at least one gold finger 22 is provided on the two side regions ofthe upper flexible plate 20A, and electrically connected with thecorresponding upper magnetic induction coil 10. Each upper connectionpad 10A is electrically connected with the corresponding upper magneticinduction coil 10, and each lower connection pad 11A is electricallyconnected with the corresponding lower magnetic induction coil 11. Inparticular, the upper connection pad 10A and the corresponding lowerconnection pad 11A are vertically aligned. Further, the dielectric layer24 is provided with at least one through-hole, which is aligned to thecorresponding upper connection pad 10A and corresponding lowerconnection pad 11A such that the upper connection pad 10A and thecorresponding lower connection pad 11A are electrically connected viathe connection plug 26, which fills up the through-hole of thedielectric layer 24.

It is preferred that the above connection plug 26 is formed of anelectrically conductive metal material such as copper, tin copper alloyor tin alloy. Particularly, the connection plug 26 possesses workabilityof thermal pressing and has a shape of ball, column or block. In otherwords, the connection plug 26 is placed between the upper connection pad10A and the corresponding lower connection pad 11A, or formed beneaththe lower surface of the upper connection pad 10A, or attached to thelower surface of the upper connection pad 10A, and then a process ofthermal pressing is performed to melt and press the connection plug 26such that the connection plug 26, the upper connection pad 10A and thecorresponding lower connection pad 11A are combined together.

Therefore, the gold finger 22, the upper magnetic induction coil 10, theupper connection pad 10A, the connection plug 26, the lower connectionpad 11A and the lower magnetic induction coil 11 of the presentembodiment are electrically connected in sequence.

The above upper magnetic induction coil 10, upper connection pad 10A,lower magnetic induction coil 11, lower connection pad 11A and goldfinger 22 are formed of the same or different electrical conductivematerial like copper, copper alloy or gold, and the dielectric layer 24is formed of a dielectric material.

As shown in FIG. 2, the adjacencies of the lower flexible plate 20B andthe lower surface of the upper flexible plate 20A are provided with therespective notched lines 23, and each notched line 23 has a trench whichrecesses upwards or inwards such that the two side regions of the upperflexible plate 20A are bendable upwards or downwards. In particular, thedielectric layer 24 is not extended to the notched line 23. That is, thenotched line 23 does not accommodate the dielectric layer 24. The wingedcoil structure thus possesses the bendable feature, provides thefunction of magnetic induction, and is applicable to the field ofmagnetic induction for coil.

Additionally, the base surfaces of the two side regions of the upperflexible plate 20A are attached to or covered by an external dielectriclayer 24A, which is formed of the same or different dielectric materialfrom the dielectric material of the dielectric layer 24, so as toprovide isolation and protection.

The winged coil structure of the first embodiment may further comprise acovering layer 25, which is configured to cover the upper surface of theupper flexible plate 20A, the lower surface of the lower flexible plate20B, and a surrounding area of the gold finger 22. Preferably, thecovering layer 25 is formed of an electrical insulation material withtransparency or opaqueness.

Further refer to FIG. 3 showing a cross sectional view of the wingedcoil structure according to the second embodiment of the presentinvention. The winged coil structure according to the second embodimentis similar to the winged coil structure of the above first embodiment,and has the same features shown in FIG. 1, which are thus omitted.

As shown in FIG. 3, one of the primary differences between the secondand first embodiments is that the winged coil structure of the secondembodiment further comprises a bottom flexible plate 20C, at least onebottom magnetic induction coil 12 and at least one bottom connection pad12A. The bottom flexible plate 20C is attached to the lower surface ofthe lower flexible plate 20B. The at least one bottom magnetic inductioncoil 12 and the at least one bottom connection pad 12A are electricallyconnected and embedded in the bottom flexible plate 20C, and configuredclose to the lower surface of the bottom flexible plate 20C. Inparticular, each bottom connection pad 12A is attached to thecorresponding lower connection pad 11A. Additionally, the bottomflexible plate 20C and the lower flexible plate 20B are of the samelateral size.

Another difference is that the winged coil structure of the secondembodiment may further comprise a covering layer 25, which is configuredto cover the surrounding area of the gold finger, the upper surface ofthe upper flexible plate 20A, the lower surface of the bottom flexibleplate 20C, instead of the covering layer 25 of the first embodimentcovering the lower surface of the lower flexible plate 20B.

Therefore, in the winged coil structure of the second embodiment, thegold finger 22, the upper magnetic induction coil 10, the upperconnection pad 10A, the connection plug 26, the lower connection pad11A, the lower magnetic induction coil 11, the bottom connection pad 12Aand the bottom magnetic induction coil 12 are electrically connected insequence.

It should be noted that the winged coil structure of the secondembodiment in FIG. 3 comprising the upper flexible plate 20A, the lowerflexible plate 20B and the bottom flexible plate 20C as a three layersstack structure is just an illustrative example, not intended to limitthe scope of the present invention. In other words, the presentinvention may substantially comprise one upper flexible plate 20A, onelower flexible plate 20B and more than one bottom flexible plate 20C.

Refer to FIG. 4 and FIGS. 5A to 5D. FIG. 4 shows a flowchartillustrating the method of manufacturing the winged coil structureaccording to the third embodiment of the present invention, and FIGS. 5Ato 5D shows the respective views for the steps of the method accordingto the third embodiment of the present invention.

As shown in FIG. 4, the method of the third embodiment generallycomprises the steps S10, S12, S14 and S16 for manufacturing the wingedcoil structure.

First, the method of manufacturing the winged coil structure of thethird embodiment begins at step S10, in which an upper flexible plate20A as shown in FIG. 5A is prepared. The upper flexible plate 20A isprovided with at least one upper magnetic induction coil 10, at leastone upper connection pad 10A, at least one gold finger 22 and at leastone connection plug 26. Further, the upper flexible plate 20A has amiddle region and two side regions bordering the middle region, and themiddle region is provided with a middle through-hole H.

Specifically, the upper magnetic induction coil 10 and the upperconnection pad 10A are electrically connected and embedded in the middleregion of the upper flexible plate 20A and close to the upper surface ofthe upper flexible plate 20A. The at least one gold finger 22 isprovided on lower surfaces of the two side regions of the upper flexibleplate 20A, and each connection plug 26 is provided on the lower surfaceof the middle region of the upper flexible plate 20A and attached to thebottom of the corresponding upper connection pad 10A. It is preferredthat the connection plug 26 has a shape of ball, column or block, and isformed of copper, tin, copper alloy or tin alloy. In addition, theconnection plug 26 has workability of thermal pressing, and is thuseasily deformed through heating and pressing.

Further, each adjacency of the lower surface of the upper flexible plate20A and the lower flexible plat 20B is provided with a notched line 23,which has a trench recessing upwards or inwards.

Next, in the step S12, a dielectric layer 24 is prepared as shown FIG.5B with a lateral size the same as a lateral size of the middle regionof the upper flexible plate 20A, and has a middle through-hole H in themiddle region of the dielectric layer 24. The step S14 is then performedby preparing a lower flexible plate 20B as shown in FIG. 5C, which has amiddle region provided with a middle through-hole H. At least one lowermagnetic induction coil 11 and at least one lower connection pad 11Awhich are electrically connected are embedded in the lower flexibleplate 20B, and particularly close to the lower surface of the lowerflexible plate 20B.

Finally, the lower flexible plate 20B, the dielectric layer 24 and theupper flexible plate 20A are sequentially stacked from bottom to top inthe step S16 to form a multiple layers stack structure as shown in FIG.5D, in which the respective middle through-holes H are aligned. Themultiple layers stack structure is thermally pressed via a pressingmold. Especially, the connection plug 26 tightly combines the upperconnection pad 10A and the lower connection pad 11A to implement goodelectrical connection.

Additionally, the method of the third embodiment may further comprise astep of forming a covering layer 25, which covers the surrounding areaof the gold finger 22, the upper surface of the middle region of theupper flexible plate 20A and the lower surface of the lower flexibleplate 20B. Thus, the winged coil structure as desired is implemented.

Further refer to FIG. 6 and FIGS. 7A to 7E. FIG. 6 shows a flowchartillustrating the method of manufacturing the winged coil structureaccording to the fourth embodiment of the present invention, and FIGS.7A to 7E shows the respective views for the steps of the methodaccording to the fourth embodiment of the present invention.

As shown in FIG. 6, the method of the fourth embodiment generallycomprises the steps S20, S22, S24, S26 and S28 for manufacturing thewinged coil structure, which are similar to the method of the thirdembodiment. The steps S20, S22 and S24 of the fourth embodiment areidentical to the steps S10, S12 and S14 of the third embodiment forpreparing the upper flexible plate 20A, the dielectric layer 24, and thelower flexible plate 20B, respectively, as shown in FIGS. 7A, 7B and 7C.Thus, the description is omitted hereinafter.

Specifically, the step S16 of the method of the fourth embodiment isperformed by preparing the bottom flexible plate 20C as shown in FIG.7C, which is attached to the lower surface of the lower flexible plate20B to form a stack body. The bottom flexible plate 20C is similar tothe lower flexible plate 20B, and has a middle region and two sideregions bordering the middle region. Also, the bottom flexible plate 20Cis provided with at least one bottom magnetic induction coil 12 and atleast one bottom connection pad 12A. The middle region of the bottomflexible plate 20C has a middle through-hole H.

Finally, a multiple layers stack structure is formed in the step S28through the process of thermal pressing, as shown in FIG. 7D. The abovestack body, the dielectric layer 24 and the upper flexible plate 20A aresequentially stacked from bottom to top, and the respectivethrough-holes H are aligned. Then, the pressing mold is employed underheating to press and combine the upper flexible plate 20A, the lowerflexible plate 20B and the bottom flexible plate 20A 20C. Therefore, theconnection plug 26 tightly combines the upper connection pad 10A and thelower connection pad 11A under thermal pressing to implement electricalconnection.

An addition step S29 is further included as shown in FIG. 7E to form acovering layer 25, which covers the upper surface of the middle regionof the upper flexible plate 20A, the lower surface of the bottomflexible plate 20C and the surrounding area of the gold finger 22. As aresult, the winged coil structure as desired is implemented.

Moreover, if the upper flexible plate 20A in FIG. 7A and the dielectriclayer 24 in FIG. 7B are larger than the lower flexible plate 20B in FIG.7C, the two side regions of the upper flexible plate 20A and thedielectric layer 24 are not supported by the lower flexible plate 20Band become floating during the process of thermal pressing in the stepS28. As a result, the final structure is easily bent and deformed, andparticularly, the gold finger 22 on the upper flexible plate 20A isseriously affected and the yield rate is greatly decreased. Therefore,to improve the yield rate, the bottom of the bottom flexible plate 20Cis supported by an auxiliary stuff 30, which is larger than or equalsthe upper flexible plate 20A, and has two projecting parts at two endsas cushion aligned to the gold finger 22. Thus, the two side regions ofthe upper flexible plate 20A and the dielectric layer 24 aresubstantially supported so as to protect the gold finger 22. Next, asshown in FIG. 7E, the auxiliary stuff 30 is removed, and the uppersurface of the upper flexible plate 20A and the lower surface of thebottom flexible plate 20C are covered by the covering layer 25.

Preferably, the above auxiliary stuff 30 is formed of silicone or pulp,and can be optionally covered by a release film, which helps directlyremove the auxiliary stuff 30.

The gold finger 22, the upper magnetic induction coil 10, the upperconnection pad 10A, the connection plug 26, the lower connection pad11A, the lower magnetic induction coil 11, the bottom connection pad 12Aand the bottom magnetic induction coil 12 in the method of the fourthembodiment are thus electrically connected in sequence.

From the above mention, one primary feature of the present invention isthat the upper magnetic induction coil, the lower magnetic inductioncoil and the bottom magnetic induction coil are provided in therespective flexible plates and combined together after the process ofthermal pressing such that the layout density of coil is greatlyincreased and the effect of magnetic induction is enhanced. As a result,the problem of alignment tolerance for the respective holes whilecombining the magnetic induction coil and the flexible plate formanufacturing traditional magnetic induction coil board in the priorarts is solved.

Another feature of the present invention is that the notched lines helpthe two side parts of the winged coil structure being bent upwards ordownwards without damage to the upper, lower and the bottom magneticinduction coils embedded. Thus, the winged coil structure of the presentinvention may easily bend upwards or downwards depending on the actualgeometrical demand, and is widely applied to various fields so as togreatly improve facility and reliability for subsequent assemblyprocesses.

Furthermore, the connection plug of the present invention possessesworkability of thermal pressing to tightly combine the respectiveconnection pads, thereby implementing good electrical connection. Theaspect of low manufacturing cost provided by the present invention isgreatly advantageous to improve industrial utility in the currentmarket.

Although the present invention has been described with reference to thepreferred embodiments thereof, it is apparent to those skilled in theart that a variety of modifications and changes may be made withoutdeparting from the scope of the present invention which is intended tobe defined by the appended claims.

What is claimed is:
 1. A method of manufacturing a winged coil structurefor providing a function of magnetic induction and a flexible andbendable feature, comprising: preparing an upper flexible plate having amiddle region and two side regions bordering the middle region, andprovided with at least one upper magnetic induction coil, at least oneupper connection pad, and at least one connection plug, the at least oneupper magnetic induction coil and the at least one upper connection padbeing electrically connected and embedded in the middle region of theupper flexible plate and close to an upper surface of the upper flexibleplate, the at least one connection plug being provided on the lowersurface of the middle region of the upper flexible plate and attached toa bottom of the corresponding upper connection pad; preparing adielectric layer with a lateral size of the dielectric layer being thesame as a lateral size of the middle region of the upper flexible plate;preparing a lower flexible plate having a middle region and two sideregions bordering the middle region, and provided with at least onelower magnetic induction coil and at least one lower connection pad, theat least one lower magnetic induction coil and the at least one lowerconnection pad being electrically connected and embedded in the middleregion of the lower flexible plate and close to a lower surface of thelower flexible plate; and performing a process of thermal pressing tosequentially from bottom to top stack and combine the lower flexibleplate, the dielectric layer, and the upper flexible plate as a multiplelayered stack structure via a press mold, the at least one connectionplug being formed of an electrically conductive metal materialconfigured to penetrate the dielectric layer, and provided between thecorresponding upper and lower connection pads such that the at least oneconnection plug combines the corresponding upper and lower connectionpads after the process of thermal pressing to form electricalconnection, wherein a notched line is provided along each adjacency ofthe lower surface of the upper flexible plate and the lower flexibleplate, the notched line has a trench recessing upwards or inwards suchthat the two side regions of the upper flexible plate are bendableupwards or downwards, and the dielectric layer is not extended to thenotched line.
 2. The method as claimed in claim 1, wherein the upperflexible plate and the lower flexible plate are formed of a resin orplastic material, and wherein the at least one connection plug is formedof copper, tin, copper alloy, or tin alloy, and has a shape of ball,column, or block.
 3. The method as claimed in claim 1, wherein basesurfaces of the two side regions of the upper flexible plate areattached to or covered by an external dielectric layer, and the externaldielectric layer is formed of a dielectric material the same as ordifferent from the dielectric material of the dielectric layer.
 4. Themethod according to claim 1, wherein a middle through-hole is providedat the middle region of the upper flexible plate, at least one middlethrough-hole is provided at a middle region of the dielectric layer, anda middle through-hole is provided at the middle region of the lowerflexible plate.
 5. The method according to claim 4, wherein therespective middle through-holes of the lower flexible plate, thedielectric layer, and the upper flexible plate are vertically aligned inthe multiple layered stack structure, and the at least one connectionplug is configured to penetrate the at least one middle through-hole ofthe dielectric layer.
 6. The method according to claim 1, wherein theupper flexible plate is further provided with at least one gold finger,and the at least one gold finger is provided on lower surfaces of thetwo side regions of the upper flexible plate.
 7. The method as claimedin claim 6, wherein the upper magnetic induction coil, the upperconnection pad, the lower magnetic induction coil, the lower connectionpad, and the at least one gold finger are formed of the same ordifferent electrical conductive material, and wherein the electricalconductive material comprises copper, copper alloy, or gold, and thedielectric layer is formed of a dielectric material.
 8. A method ofmanufacturing a winged coil structure for providing a function ofmagnetic induction and a flexible and bendable feature, comprising:preparing an upper flexible plate having a middle region and two sideregions bordering the middle region, and provided with at least oneupper magnetic induction coil, at least one upper connection pad, and atleast one connection plug, the at least one upper magnetic inductioncoil and the at least one upper connection pad being electricallyconnected and embedded in the middle region of the upper flexible plateand close to an upper surface of the upper flexible plate, the at leastone connection plug being provided on the lower surface of the middleregion of the upper flexible plate and attached to a bottom of thecorresponding upper connection pad; preparing a dielectric layer with alateral size of the dielectric layer being the same as a lateral size ofthe middle region of the upper flexible plate; preparing a lowerflexible plate having a middle region and two side regions bordering themiddle region, and provided with at least one lower magnetic inductioncoil and at least one lower connection pad, the at least one lowermagnetic induction coil and the at least one lower connection pad beingelectrically connected and embedded in the middle region of the lowerflexible plate and close to an lower surface of the lower flexibleplate; preparing a bottom flexible plate attached to the lower surfaceof the lower flexible plate to form a stack body, the bottom flexibleplate having a middle region and two side regions bordering the middleregion, and provided with at least one bottom magnetic induction coiland at least one bottom connection pad, the at least one bottom magneticinduction coil and the at least one bottom connection pad beingelectrically connected, embedded in the middle region of the bottomflexible plate, and close to a lower surface of the bottom flexibleplate; and performing a process of thermal pressing to sequentially frombottom to top stack and combine the stack body, the dielectric layer,and the upper flexible plate as a multiple layered stack structure via apress mold, the at least one connection plug being formed of anelectrically conductive metal material, configured to penetrate thedielectric layer, and provided between the corresponding upper and lowerconnection pads such that the at least one connection plug combines thecorresponding upper and lower connection pads after the process ofthermal pressing to form electrical connection, wherein a notched lineis provided along each adjacency of the lower surface of the upperflexible plate and the lower flexible plate, the notched line has atrench recessing upwards or inwards such that the two side regions ofthe upper flexible plate are bendable upwards or downwards, and thedielectric layer is not extended to the notched line.
 9. The method asclaimed in claim 8, wherein the upper flexible plate, the lower flexibleplate, and the bottom flexible plate are formed of a resin or plasticmaterial, and wherein the at least one connection plug is formed ofcopper, tin, copper alloy, or tin alloy, and has a shape of ball,column, or block.
 10. The method according to claim 8, wherein a middlethrough-hole is provided at the middle region of the upper flexibleplate, at least one middle through-hole is provided at a middle regionof the dielectric layer, a middle through-hole is provided at the middleregion of the lower flexible plate, and a middle through-hole isprovided at the middle region of the bottom flexible plate, therespective middle through-holes of the bottom flexible plate.
 11. Themethod according to claim 10, wherein the lower flexible plate, thedielectric layer, and the upper flexible plate are vertically aligned inthe multiple layered stack structure, and the at least one connectionplug is configured to penetrate the at least one middle through-hole ofthe dielectric layer.
 12. The method according to claim 8, wherein theupper flexible plate is further provided with at least one gold finger,and the at least one gold finger is provided on lower surfaces of thetwo side regions of the upper flexible plate.
 13. The method as claimedin claim 12, wherein the upper magnetic induction coil, the upperconnection pad, the lower magnetic induction coil, the lower connectionpad, the bottom magnetic induction coil, the bottom connection pad, andthe at least one gold finger are formed of the same or differentelectrical conductive material, and wherein the electrical conductivematerial comprises copper, copper alloy, or gold, and the dielectriclayer is formed of a dielectric material.
 14. The method as claimed inclaim 12, wherein base surfaces of the two side regions of the upperflexible plate are attached to or covered by an external dielectriclayer, and the external dielectric layer is formed of a dielectricmaterial the same as or different from the dielectric material of thedielectric layer.
 15. The method according to claim 12, furthercomprising: prior to the process of thermal pressing, supporting abottom of the bottom flexible plate by an auxiliary stuff, wherein theauxiliary stuff is larger than or equal to the upper flexible plate andhas two projecting parts at two ends aligned to the at least one goldfinger, so that the two side regions of the upper flexible plate and thedielectric layer are supported by the auxiliary stuff during the processof thermal pressing; removing the auxiliary stuff after the process ofthermal pressing; and covering a covering layer on the upper surface ofthe upper flexible plate, the lower surface of the lower flexible plate,and a surrounding area of the at least one gold finger, wherein thecovering layer is formed of an electrical insulation material withtransparency or opaqueness.